In a conventional wireless communication system, a Gaussian channel environment is assumed for an interference signal in order to perform a decoding operation with a low complexity. In the conventional wireless communication system, a quadrature amplitude modulation (QAM) series of modulation scheme is used in order that a characteristic of an interference signal becomes maximally close to Gaussian.
However, channel capacity of a non-Gaussian channel is greater than channel capacity of a Gaussian channel, so, if an accurate decoding operation is performed, a decoding performance better than a decoding performance on the Gaussian channel may be acquired on the non-Gaussian channel.
Modulation schemes among modulation schemes which modulate a related signal thereby an interference signal has a non-Gaussian characteristic are a frequency shift keying (FSK) scheme and a hybrid FSK and QAM modulation (FQAM) scheme.
The FQAM scheme is a hybrid modulation scheme in which the QAM scheme and the FSK scheme are combined, and has a high spectral efficiency of the QAM scheme and a characteristic of the FSK scheme in which a signal is modulated thereby an interference signal has a non-Gaussian characteristic.
However, in the FQAM scheme, it may not be possible that a bit-to-symbol mapping scheme is effectively used. So, if the FQAM scheme is used, a non-binary code with a large alphabet size should be used with the FQAM scheme in order to acquire a good bit-to-symbol mapping performance. Generally, a complexity of the non-binary code exponentially increases if an alphabet size increases, so there may be a need for a high processing complexity in order to enhance a performance of the FQAM scheme.
There may be a need for a method of transmitting/receiving a signal thereby enhancing a bit-to-symbol mapping performance and decreasing a processing complexity in a wireless communication system supporting a FQAM scheme.